Cast cutting device



March 24, 1959 G. R. FRENCH 2,878,806

CAST CUTTING DEVICE Filed March 4, 1955 2 sheets-sheet 1 /7 /5 /5 /0 22 /7 l /5 jmmmw f JNVENTOR. @mvo/V e. FAMA/c# March 24, 1959 G. R. FRENCH 2,878,806

v CAST CUTTING DEVICE Filed March 4, 1955 2 Sheets-Sheet 2 f f f i #AH Hlm m11 5 u.' l Il 1| Unite VThis invention relates to a cast cutting device, and more particularly to a cast cutting assembly adapted to be wrapped within a cast as the same is applied to a patient and, after the cast no longer is needed, used to cut the cast from the patient without possibility of injury.

Cast cutting devices of the type in which a flexible saw is wrapped within a cast as it is applied to the patient are subject to several important deliciences. One very important deficiency is that the esh protecting member employed to prevent the saw from injuring the patient is frequently so inflexible as to be difficult to use, particularly where the cast is applied to a curved area such as the knee, elbow or skull. In order to permit application of casts to such curved portions of the body, it is necessary that the flesh protecting member be ilexible not only upwardly and downwardly but also laterally, and furthermore that the member be readily susceptible of a substantial amount of twisting.

Another important deficiency in present cast cutting assemblies is that it is dillicult for a person removing the cast to find initially the ends of the flexible saw unless such ends are exposed in such a way as to be relatively dangerous, and to make them subject to corrosion and damage.

In view of the above factors characteristic of cast cutting devices of the type indicated, it is an object of the present invention to provide a cast cutting assembly in which the kflesh protecting member is highly flexible and has at least three degrees of freedom, yet is completely adequate to eliminate any possibilities that the saw will injure the patient as the cast is worn or during its removal.

Another object of the invention is to provide a cast cutting assembly in which the flexible saw is substantially longer than the flesh protecting member with which it is associated, and a moisture resistant envelope or casing is mounted around not only the flesh protecting member but also around the projecting saw ends `in order to prevent corrosion and damage thereto, and injury to the patient.

An additional object is to provide a channel member which serves as a iiesh protecting strip in a castrcutter assembly, said channel member being formed from a zigzag blank so designed that the resulting channel will be highly exible in any direction and will be susceptible of substantial twisting.

These and other objects and-advantages of the invention will be more fully set forth in the following specilication and claims considered in connection with the attached drawings to which they relate.

In the drawings:

Figure l is a pictorial view illustrating the cast cutter assembly as used in an arm cast, portions of the cast being broken away to better illustrate the cutter assembly;

Figure 2 is an enlarged longitudinal fragmentary view illustrating the cast cutting device as employed in the cast ofFigure l.;

Figure 3 corresponds to Figure 2 but shows the cutter tates Patent assembly during the sawing operation to effect cutting of the cast, the ends of the protective envelope being 'broken and handles being applied to the saw ends so that the saw may be reciprocated to elect cutting;

Figure 4 is a transverse sectional View taken along line 4-4 of Figure 2;

Figure 5 is a plan view showing the blank for a flesh protecting channel of a type which may be employed in the assembly illustrated in Figures 1-4;

Figure 6 illustrates the blank of Figure 5 after its forming into the completed channel;

Figure 7 illustrates a modified form of channel corresponding generally to the one shown in Figure 6 but having annular apertures in the channel flanges instead of semicircular notches therein;

Figure 8 shows a zigzag kblank for another modified Figure ll illustrates the blank of Figure l0 after formi ing into the completed channel; p

Figure l2 illustrates a flexible wire bent into a zigzag conformation to form a blank for Vanother modified form of channel;

Figure 13 illustrates the blank o-f Figure l2 after bending into the completed channel; and

Figure 14 illustrates a further modified form of channel.

Referring now to the drawing, and particularly to Figures l-4 thereof, the cast cutter assembly is indicated generally by the reference numeral 10 and is illustrated as Wrapped intoa conventional plaster cast 11, the latter being shown as applied to the arm 12 of a patient although it could, of course, be vapplied to any other part of the body. The cutter assembly 10 comprises aflexible saw element 13, a flesh protective channel member 14, and a water resistant envelope 15 enclosing both the saw element and channel. Suitable handles or hooks 16 are connected to the ends 17 of saw element 13 when it is desired to reciprocate the saw and cut the cast as shown in Figure 3.

The liexible saw element 13 may be of any suitable type, such as spiral, jewelers, scroll, or Gigli, a spiral saw being preferable. As illustrated, the saw 13 is substantially longer than-the flesh protective member 14, so'that the saw ends 17 extend substantial distances from each end of the flesh protector. As best shown in Figure 4, the flesh protector 14 is a channel member which opens outwardly, or away from the body `portion to which the cast is applied. The web of the channel then serves to prevent any abrasive or injurious action between saw 13 `and the patient during wearing of the cast, the

channel 14 being formed of a flexible abrasion resistant highly flexible plastic, desirably a suitable vinyl resin, and y 1s made from sheet stock by providing a joint at 19 (Figure 4) through application of heat or other means. The

envelope serves the very important purpose of protecting y the saw and channel from 4moist plaster so thatnocorp rosion or other adverse elects can result, of preventing Patented Mar. 24, 19519v venience or injury tothe patient and without possibility of damage to or dulling of the saw.

The cast cutter assembly is formed by laying the saw 13 in the flesh protective channel 14, and then inserting these elements into an open end of envelopelS. Preferably, the ends of envelope 15 are then sealed around the saw ends 17 through application of heat.

In applying a cast with the cast cutter assembly 10, one or two layers of plaster, indicated at 21 and which may include sheet wadding if desired, are first applied to the arm 12 or other body member. The assembly 10 is then mounted over the inner plaster layers 21 and so arranged that the web of channel 14 is adjacent the body member, and the channel flanges open outwardly. The outer layers 22 of plaster are then applied as illustrated, and the cast is completed.

When it is desired to remove the cast 11, the handles 16 are suitably connected to saw ends 17 after making openings in the ends of envelope 15. In this connection it is pointed out that access to the saw ends 17 is without difliculty, yet these ends are protected during wearing of the cast as stated heretofore. -It is then merely necessary to pull back and forth on handles 16 to reciprocate blade 13, which operates to cut through both the envelope 15 and the main body or outer portion 22 of cast 11. cutting and removal of the outer cast portion, the relatively thin inner portion 21 is readily cut as by scissors, and the cast removal operation is complete.

Referring next to Figures and 6, there is illustrated one form of esh protective channel, the blank being shown in Figure 5 and the completed formed channel in Figure 6. This channel has been given the reference numeral 14a and may be seen to comprise a web 26 and flanges 27. Provided at axially spaced points in the free edges of anges 27 are semicircular openings or notches 28 which serve to increase the flexibility of the channel and facilitate its bending upwardly and downwardly, that is to say transversely of web 26. Provided at axially spaced points in web 26 are annular openings 29 which also aid in increasing the flexibility of the channel as well as lightening it. The channel 14a is preferably formed of sheet stock of a lightweight, flexible metal such as aluminum, by first blanking to produce the structure shown in Figure 5, and then bending flanges 27 vertically of web 26 to form the finished product shown in Figure 6. The completed channel is then assembled with saw 13 and envelope 15 and performs the functions described above.

In Figure 7 there is illustrated a modified form of channel, indicated at 14b, which is provided with annular openings 31 in both its web 32 and flanges 33. This channel 14b functions generally the same as the one shown in Figure 6, except that the location of the openings 31 in flanges 33 results in somewhat lessened ilexibility as compared to channel 14a.

In Figures 8 and 9 there is shown a further modified form of channel which has been given the reference numeral 14e, the blank being shown in Figure 8 and the completed channel in Figure 9. It is emphasized that lthe blank is a strip of sheet -metal provided with staggered V-shaped notches 36 the apexes 37 of which lie generally along a line parallel to and midway between the edges 38 of the blank. It follows that when the bending operation is performed along the dashed lines 39 in order to form the completed channel, having a web 41 and flanges 42, the apexes 37 will be generally at the center or axis of the web.

The construction shown in Figures 8 and 9 4is advantageous in that the channel 14e may be bent upwardly and downwardly with extreme ease due to the fact that the opposed edges of the respective notches 36 are spaced from each other and extend for the full height of channel After v provided in that the channel may be bent sideways due to the fact that the apexes 37 extend into theweb 41 instead of terminating at bending lines 39. The described construction is also such as to facilitate twisting of the channel.

Illustrated in Figures and ll is a form of channel corresponding generally to that shown in Figures 8 and 9, and which has been given the same reference numerals 'i except that the apexes 37 extend clear across the web 41 flanges 42. Furthermore, a second degree offreedom is to the lines 39 of bending between the web and the flanges 42. This channel has been given the reference numeral 14 since it is the one illustrated in the assembly shown in vFigures 1-4 and is a form allowing, to a great extent, `three degrees of flexibility or freedom.

It will be observed that if the channel 14 is bent upwardly or downwardly the spaced edges of the portions of notches 36 which lie in flanges 42 will move toward or away from each other, which means that the resistance to such bending will be extremely slight. If the channel 14 is bent sidewise, that is to say about an axis perpendicular to the plane of web 41, the portions of the web which forrnthe apexes 37 (and adjacent regions) of notches 36 will move toward or away from each other depending 4upon the direction of bending, and the resistance to the la substantial amount of twisting is rendered possible, this beingV extremely desirable for application of a cast to the A knee, elbow or similar curved portions of the body.

` Proceeding next to Figures l2 and 13 a channel 14d is illustrated and which, instead of being formed of sheet "metal, is manufactured from a single piece of metal wire 46. As shown in Figure 12, the wire 46 is first bent into" zigzag form and in a common plane. Thereafter, bending transverse to said common plane is performed along bend'lines l47 to result in a channel having flange portions '48 and a web portion 49. It will be apparent that the resulting channel is extremely flexible in any direction, making it highly suitable for applications in which the cast is sharply curved or contoured such as when applied to the skull.

Proceeding next to Figure 14, there is shown a channel 14e again constructed of sheet metal stock as in the case of the structures shown in Figures 5-11. Channel 14e is manufactured by providing a strip of sheet metal and slitting the edges thereof transversely at spaced points, the bases of the slits lying along bend lines 51. The slit portions of the blank are then bent perpendicularly along lines 51 to form a web 52 and flanges, the latter being formed of a large number of ears 53. It is pointed out that the ears 53 are not spaced longitudinally of the web 52, but instead are closely adjacent each other at their edges.

In order to permit upward and downward flexing of the channel 14e, alternate ears 53 are bent inwardly from the vertical as illustrated, so that overlapping between .the inwardly bent ears and the adjacent ears may take lsign herein shown other than as defined in the appended claims.

I claim:

1. A cast cutting assembly, which comprises a flexible land abrasion resistant flesh protector member, a flexible saw blade mounted longitudinally of said flesh protector member and projecting beyond the ends thereof, and a.

one-piece sealed water-proof seamless flexible envelope enclosing said flesh protector member and the entire length of said saw, said envelope serving to prevent contact of moist plaster with said esh protector and with said saw, to prevent said saw from being imbedded in plaster, to protect the exposed ends of said saw `and prevent injurious contact between said exposed ends and the wearer of a cast with which the cutting assembly is associated and to prevent moisture from contacting and corrodng the saw.

2. The invention as claimed in claim l, in which said tiesh protector is a flexible channel enclosing said saw blade on three sides and formed from metal stripping having V-shaped notches extending toward one another from the opposite edges of said stripping.

3. A cast cutting assembly, which comprises a channel member formed of abrasion resistant exible material, a flexible saw wire mounted longitudinally within said channel member and projecting beyond the ends thereof to expose the end portions of said saw, and a seamless water-proof plastic tubular enclosure surrounding said channel and the projecting end portions of said saw, the opposite ends of said envelope being sealed closed and serving to prevent contact of moist plaster with said ilesh protector and saw, to prevent said saw from being imbedded in plaster, and to protect said saw against corrosion and to prevent injurious contact between said exposed saw ends and the wearer of a cast with which the cutting assembly is associated.

4. The invention as claimed in claim 3, in which said channel member is formed with openings serving extending crosswise of its side walls and connecting web from alternately spaced points along the opposite lateral edges thereof and to increase the exibility thereof.

5. The invention as claimed in claim 3, in which the anges of said channel member are formed with generally V-shaped staggered notches, the apexes of said notches extending into the channel web.

6. The invention as claimed in claim 5, in which the apex of each notch extends to the channel flange opposite the channel llange in which the main body of said notch is formed.

7. The invention as claimed in claim 3, in which said channel member is formed of a piece of wire bent in general zigzag arrangement.

8. The invention as claimed in claim 3, in which the anges of said channel member are slit vertically from the web thereof, and alternate portions of said llanges are bent at a slight angle relative to the planes of the remaining alternate portions of said ilanges.

9. In a cast cutter assembly, a sheet metal channel member the web and anges of which are formed with staggered generally V-shaped notches, the wide portion or base of each notch being at the free edge of one of said flanges, and the apex of each notch being disposed generally at the junction of said web and the other of said flanges.

10. In a cast cutter assembly, a sheet metal channel member the anges of which are slit vertically from the web at spaced points, alternate portions of said flanges being bent at a slight angle relative to the planes of the remaining alternate portions of said anges.

11. In a cast cutting assembly, a flesh protector comprising an elongated channel-shaped strip of rigid but flexible material having a central web and a pair of parallel side anges upstanding therefrom, said web and said anges being formed by zig-zag arranged elements of substantially uniform cross-section throughout the length thereof and integrally connected together to form a lightweight protector of substantially uniform flexibility from end to end thereof.

12. An article of manufacture for use in concealing a saw blade and forming an open-topped channel-shaped enclosure therefor, said article of manufacture being adapted to be embedded along with an encased saw blade within a plaster-of-paris-type cast encircling a part of the human body, said article comprising an elongated channel-shaped flexible member formed of V-shaped elements, said V-shaped elements being arranged in sideby-side relation with the ends of the legs of adjacent elements integral with one another, and said integral ends and the remotely positioned ends of said elements being bent toward one another to form the opposite sides of said exible channel-shaped member.

13. An article of manufacture for use` in concealing a saw blade and forming an open-topped channel therefor within a plaster-of-paris-type cast encircling a part of the human body, said article comprising an elongated strip of thin rigid material, said strip having notches cut thereinto from spaced points along the opposite lateral edges of said strip, adjacent ones of said notches being offset longitudinally of said strip with the apexes thereof terminating short of the opposite lateral edge of the strip, the opposite edges of said strip being upturned from the longitudinal central portion of the strip to provide an open-topped channel of suicient internal cross section to conceal a miniature saw blade therewithin and said notches rendering said channel readily exible by the lingers.

14. An article of manufacture as dened in claim 13 wherein the junctions of the opposite upturned sides of said channel with the intervening web portions of said strip lie adjacent the apexes of said notches.

15. An article of manufacture as defined in claim 13 wherein the apexes of said notches terminate adjacent the longitudinal axis of said strip.

16. An aritcle of manufacture as defined in claim 13 wherein said strip is formed from a metal highly resistant to corrosion from body vapors .as well as from materials employed in the making of casts for portions of the human body.

References Cited in the le of this patent UNITED STATES PATENTS 2,187,175 Prosperi Jan. 16, 1940 2,519,520 Waxlax a Aug. 22, 1950 FOREIGN PATENTS 72,145 Austria July 25, 1916 587,069 Germany Oct. 28, 1933 278,766 Switzerland Oct. 3, 1951 UNITED STATES PATENT oEEICE CERTIFICATE 0F CORRECTION Patent No., 2,878,806 March 24, l959 Gordon R French It is herebjr `certified that error appears in the -printed specification of the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 5, line 3l, claim 2+, strike out "serving" and insert the same 'before "to increase", in line 34, same' claim',

Signed and sealed thisv 28th day of July 1959.

(SEAL) Attest:

KART- H, XLINE Attesting Officer ROBERT C. WATSON Commissioner of Patents 

